With regard to the suppository, I would still continue down the rabbit hole to find the core fear. When she gives you an answer, you continue going further until you reach the bottom. For example, “what’s the hardest part (or scariest) part about getting a suppository? If it how it feels is the main issue, roleplaying is nice, but not addressing the main issue.
You won’t always do challenges for fears or struggles, sometimes you do some reframing (especially when it is anxiety based).
The fear of missing items or “possibly needing them in the future” are common thoughts for people who struggle with hoarding. I don’t know how old she is, but with kids who have these issues (even with my own son), I explained hoarding in a kid friendly way and limited “saving” unnecessary things to one drawer. It was a process and it took some time to get to that point, but now at 12 hoarding is not an issue at all for him.
Here are some resources on hoarding in kids that might help further:
-Podcast for you:
-Youtube video for kids:
Indecision is also a common anxiety trait. It is helpful to teach her that she will never have a 100% great feeling about a choice, because there will always be other options. The key is to just embrace what you decided and sit with the uncomfortable feeling the decision brought you (not wavering).
I made a kids YouTube video on that topic as well: